How much more pressure does a 250 lb person exert on the ground than a 120 lb person if they are both standing on one foot with area 16 in2?

Answer:

57.124.18 Pascals

Explanation:

The pressure that each person exerts on the ground is given by:

Pressure = force/area

The force that each person exert is given by:

Force = mass (kg) x acceleration due to gravity (10 m/s2)

1 lb = 0.4536 kg, hence;

250 lb person = 113.398 kg

120 lb person = 54.431 kg

Force exerted by the 250 lb person = 113.398 x 10 = 1133.98 kg/m2

Force exerted by 120 lb person = 54.431 x 10 = 544.31 kg/m2

16 inch2 = 0.0103226 m2

Pressure exterted by 250 lb person = 1133.98/0.0103226

                           = 109,854.11 pascals

Pressure exerted by 120 lb person = 544.31/0.0103226

                           = 52,729.93 Pascals

Difference in pressure = 109,854.11 - 52,729.93

                               = 57,124.18 Pascals

Hence, a 250 lb person will exert 57.124.18 Pascals pressure more than a person of 120 lb on a foot with a 16 inch2 area.

1. What kinds of metals are REALLY reactive? why?
2. What kinds of non-metals are REALLY reactive? why?
3. What group on the periodic table doesn’t react at all? why?

A teacher asks students to describe the physical properties of 10 mL of vinegar and 10 mL of milk. When the students finish listing the physical properties in their science notebooks, the teacher pours the vinegar and milk into the same beaker. The students are surprised to see a white solid substance form within the beaker as the two substances are combined.

What occurs within the beaker as the teacher mixes the vinegar and milk?
1. A chemical change that produces a precipitate
2. A physical change that creates a new substance
3. A physical change that produces a precipitate
4. A chemical change that produces no new substances